Nunjucks loader for webpack

require precompiled templates in webpack
supports extends and include
resolves template dependencies using require
bundles the nunjucks-slim browser runtime
use the version of nunjucks you want to as a peer dependency
supports experimental Jinja compatibility

Usage

Recommended configuration

Install: npm install nunjucks-loader --save

Add to webpack.config to process all .njk and .nunjucks files:

// file: webpack.config.js
module.exports = {

    entry: './src/entry.js',

    output: {
        path: __dirname,
        filename: 'bundle.js'
    },

    module: {
        loaders: [
            {
                test: /\.(njk|nunjucks)$/,
                loader: 'nunjucks-loader'
            }
        ]
    }

};

Then use it in your module code without the nunjucks! prefix:

// file: src/entry.js
var tpl = require('./views/page.njk');
var html = tpl.render({ message: 'Foo that!' });

Inline configuration (not recommended)

If using the inline configuration (below), references inside of templates to other files (parents, imports etc) may not resolve correctly - hence it's preferable to use the webpack.config method above.

var tpl = require("nunjucks!./views/page.njk");
var html = tpl.render({ message: 'Foo that!' });

webpack.target = 'node'

The 2.x versions of this loader do not support node/UMD bundles.

If you need to support node or UMD with the bundle, the 1.x version (npm install nunjucks-loader@1.0.7) supports these targets.

Filters and extensions

A require filter is added by this package that allows you to use webpack to resolve file references. Eg.

{# use the raw-loader to replace 'readme.txt' with the contents of that file #}
{{ 'raw!readme.txt' | require }}

A custom nunjucks.Environment is used by the loader, to configure the nunjucks environment:

To pass nunjucks.Environment options, add a opts key to the nunjucks loader query in webpack.config.js
Create a file that will configure the environment. This should export a function that receives the nunjucks environment as its first argument.
Add a config key to the nunjucks-loader query in webpack.config.js
Add an optional quiet key to the loader query in webpack.config.js to suppress precompile warnings (see below)

// file: src/nunjucks.config.js
module.exports = function(env){
    
    env.addFilter('asyncFoo', function(input, done){
        setTimeout(function(){
            done('[asyncFoo] ' + input);
        }, 1000)
    }, true);
    
    // env.addExtension(...) etc
}

// file: webpack.config.js
module.exports = {

    entry: './src/entry.js',

    output: {
        path: __dirname,
        filename: 'bundle.js'
    },

    module: {
        loaders: [
            {
                test: /\.(njk|nunjucks)$/,
                loader: 'nunjucks-loader',
                query: {
                    config: __dirname + '/src/nunjucks.config.js'
                }
            }
        ]
    }
};

If using async filters or custom extensions with nunjucks, they must be available before the template is precompiled. If the nunjucks config file depends on webpack resolve (such as loaders or custom module paths), the custom filters/extensions will not be available at precompile time. When/if this happens, you will receive the following warning in the console:

Cannot configure nunjucks environment before precompile

When using webpack resolve with the environment config and not using async filters or custom extensions, the warning can be safely ignored - standard filters are still added to the environment at runtime.

To remove the warning, pass the quiet option in the loader query. eg:

// file: webpack.config.js
module.exports = {

    module: {
        loaders: [
            {
                test: /\.(njk|nunjucks)$/,
                loader: 'nunjucks-loader',
                query: {
                    config: __dirname + '/src/nunjucks.config.js',
                    quiet: true // Don't show the 'Cannot configure nunjucks environment before precompile' warning
                }
            }
        ]
    }
};

Path resolution

This loader modifies the way nunjucks resolves dependencies (eg extends, import and include) to work correctly with webpack. As a result, you may use require style relative paths in your templates. Add a resolve.root key to webpack.config.js to resolve your templates without using relative paths.

// file: webpack.config.js
module.exports = {
    resolve: {
        root: [
            __dirname,
            __dirname + '/src/views'    // Resolve templates to ./src/views
        ]
    }
}

Alternatively, a root query parameter can be passed to the loader to set the root template directory.

// webpack.config.js
module.exports = {
    module: {
        loaders: [
            {
                test: /\.(nunj|nunjucks)$/,
                loader: 'nunjucks-loader',
                query: {
                    root: __dirname + '/path/to/templates'
                }
            }
        ]
    }
}

Jinja/Python compatibility

If experimental support for Jinja compatibility is desired, pass the jinjaCompat option in the loader query. eg:

// file: webpack.config.js
module.exports = {

    module: {
        loaders: [
            {
                test: /\.(nunj|nunjucks)$/,
                loader: 'nunjucks-loader',
                query: {
                    jinjaCompat: true
                }
            }
        ]
    }
};

This option will not provide full Jinja/Python compatibility, but will treat True/False like true/false, and augment arrays and objects with Python-style methods (such as count, find, insert, get, and update). Review the jinja-compat source to see everything it adds.

Tests

npm run test Navigate to http://localhost:8080/test

wellcometrust/nunjucks-loader